Condensable vapor, such as water vapor, has been used to perform a variety of medical procedures. For example, U.S. Pat. No. 7,993,323 describes a medical vapor generator system that generates and delivers condensable vapor to perform lung volume reduction as an emphysema therapy. Other early medical vapor generators are described in US 2002/0177846 and US 2009/0216220. These publications describe therapeutic methods including treating, e.g., the liver, breast, gall bladder, stomach, pancreas, colon, urinary bladder, prostate, bone, vertebrae, eye and brain.